Recombinant Human IFN-alpha-4A Protein, CF

Recombinant Human IFN-alpha-4A Protein (Catalog # 10998-IF) demonstrates anti-viral activity in HeLa human cervical epithelial carcinoma cells infected with encephalomyocarditis (EMC) virus. The ED50 for this effect is 1.00‑20.0 pg/mL

2 μg/lane of Recombinant Human IFN-alpha-4A Protein (Catalog # 10998-IF) was resolved with SDS-PAGE under reducing (R) and non-reducing (NR) conditions and visualized by Coomassie® Blue staining, showing bands at 17-23 kDa, under reducing conditions.

• Reactivity: Hu
• Applications: Bioactivity
• Format: Carrier-Free

Recombinant Human IFN-alpha-4A Protein, CF Summary

• Details of Functionality: Measured in anti-viral assays using HeLa human cervical epithelial carcinoma cells infected with encephalomyocarditis (EMC) virus. Meager, A. (1987) in Lymphokines and Interferons, a Practical Approach. Clemens, M.J. et al. (eds): IRL Press. 129. The ED₅₀ for this effect is 1.00-20.0 pg/mL.
• Source: Human embryonic kidney cell, HEK293-derived human IFN-alpha 4 protein
  Cys24-Asp189
• Accession #: P05014.2
• N-terminal Sequence: Cys24
• Protein/Peptide Type: Recombinant Proteins
• Purity: >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining.
• Endotoxin Note: <0.10 EU per 1 μg of the protein by the LAL method.

Applications/Dilutions

• Dilutions:
  • Bioactivity
• Theoretical MW: 19 kDa.
  Disclaimer note: The observed molecular weight of the protein may vary from the listed predicted molecular weight due to post translational modifications, post translation cleavages, relative charges, and other experimental factors.
• SDS-PAGE: 17-23 kDa, under reducing conditions.

Packaging, Storage & Formulations

• Storage: Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
  • 12 months from date of receipt, -20 to -70 °C as supplied.
  • 1 month, 2 to 8 °C under sterile conditions after reconstitution.
  • 3 months, -20 to -70 °C under sterile conditions after reconstitution.
• Buffer: Lyophilized from a 0.2 μm filtered solution in PBS.
• Purity: >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining.
• Reconstitution Instructions: Reconstitute at 100 μg/mL in PBS.

Notes

This product is produced by and ships from R&D Systems, Inc., a Bio-Techne brand.

Alternate Names for Recombinant Human IFN-alpha-4A Protein, CF

• IFNA4
• IFNalpha 4
• IFN-alpha 4
• IFN-alpha-4
• IFN-alpha4a
• INFA4
• interferon alpha-4
• Interferon alpha-4B
• Interferon alpha-76
• Interferon alpha-M1
• interferon, alpha 4
• MGC142200

Background

Interferons (IFN) are a family of cytokines with potent antiviral, antiproliferative and immunomodulatory properties, classified based on their binding specificity to cell surface receptors (1). Human IFNA2 was originally cloned in the early ‘80s and now more than a dozen closely related IFN alpha subtypes have been identified in both the human and mouse genome, each sharing about 80% amino acid (aa) sequence homology (2-4). Structurally, type I IFNs belong to the class of five helical‑bundle cytokines, with the IFNA subtypes containing 2 conserved disulfide bonds (5). The mature human IFNA4 shares 57% aa sequence identity with mouse IFNA4. Two variants of human IFNA4 are known to exist, IFNA4a and IFNA4b, which only differ by residues at aa position 74 and 137 (6). The type I IFNs bind to the interferon alpha receptor (IFNAR), which consists of two subunits: IFNAR1 (alpha -subunit) and IFNAR2 (beta -subunit) (7, 8). Individual IFNA subtypes are known to display unique efficacies to viral protection, and IFNA4 has been shown to be an intermediate inducer of IFN-stimulated genes and anti-viral protection (9). Mutations in IFNA4 can cause impaired function and lead to Crohn's disease susceptibility (10). IFNA4 also exhibits strong antiviral effects against SARS-CoV-2 (11).

1. Pestka, S. et al. (1987) Annu Rev Biochem. 56:727.
2. Goeddel, D.V. et al. (1980) Nature 287:411.
3. Matsumiya, T. et al. (2007) J. Immunol. 179:4542.
4. Schreiber, G. and J. Piehler (2015) Trends Immunol. 36:139.
5. Wittling, M.C. et al. (2021) Front Immunol. 11:605673.
6. Hussain, M. et al. (1997) J. Interferon Cytokine Res. 17:559.
7. van Pesch, V. et al. (2004) J. Virol. 78:8219.
8. James, C.M. et al. (2007) Vaccine. 25(10):1856.
9. Moll, H.P. et al. (2011) Cytokine. 53:52.
10. Xiao, C.X. et al. (2015) Sci Rep 5:10514.
11. Schuhenn, J. et al. (2022) PNAS https://doi.org/10.1073/pnas.2111600119.

Bioinformatics

• Uniprot:
  • P05014.2()